Gunnar Berge, the Nobel committee chairman, contrasted the 78-year-old Carter's success in using diplomacy to negotiate peace between Egypt and Israel with Bush's threats to use force against Iraq.
''It (the award) should be interpreted as a criticism of the line that the current administration has taken,'' he said. ''It's a kick in the leg to all that follow the same line as the United States.''
The Norwegian Nobel Committee cited Carter's ''vital contribution'' to the Camp David Accords between Israel and Egypt and his efforts in conflict resolution on several continents and the promotion of human rights after his presidency.
''In a situation currently marked by threats of the use of power, Carter has stood by the principles that conflicts must as far as possible be resolved through mediation and international co-operation based on international law, respect for human rights, and economic development,'' the citation said.
The award is worth $1 million.
Bush called his predecessor to congratulate him and the two spoke for a few minutes.
''It was a friendly conversation,'' White House press secretary Ari Fleischer said, adding that Bush was ''pleased to be able to congratulate a former American president on winning such a prestigious award.''
There was no immediate White House comment on Berge's remarks.
Although the committee has often used the prize to send a political message, it rarely makes such a direct comment. And Berge's statements were not approved by other members of the committee.
The citation did not mention Iraq and other members of the Nobel committee distanced themselves from Berge's criticism of Bush, saying it was his own opinion and had not been part of the discussions leading to the prize.
''In the committee, we didn't discuss what sort of interpretation of the grounds there should be. It wasn't a topic,'' committee member Hanna Kvanmo was quoted as telling the Norwegian news agency NTB.
In a statement posted on the Carter Center's Web site, the 39th president said, ''My concept of human rights has grown to include not only the rights to live in peace, but also to adequate health care, shelter, food, and to economic opportunity. I hope this award reflects a universal acceptance and even embrace of this broad-based concept of human rights.''
Earlier, Carter told CNN that when he left the White House he decided to ''capitalize on the influence I had as the former president of the greatest nation of the world and decided to fill vacuums.'' Carter refused to comment on Bush's Iraq policy.
Carter has said his most significant work has been through the Carter Center, an ambitious, Atlanta-based think tank and activist policy center he and wife, Rosalynn, founded in 1982 and which celebrates its 20th anniversary this year.
Perhaps his crowning achievement as president was the peace treaty he negotiated between Egyptian President Anwar Sadat and Israeli Premier Menachem Begin. Carter kept them at Camp David for 13 days in 1978 to reach the accord; Sadat and Begin shared the Nobel Peace Prize.
The Nobel committee said Carter, who was in the White House from 1977-1981, didn't share in that prize because he wasn't nominated in time.
The five-member committee made its decision last week after months of secret deliberations as it sought the right message for a world still dazed by the Sept. 11 terror attacks, the war on terrorism that followed and concern about a possible U.S. military strike against Iraq.
Afghan President Hamid Karzai, one of this year's nominees, had called a press conference in Kabul in advance of the announcement, but ended up congratulating Carter.
''He deserved it better than I, and he won it, and I'll try for next year,'' he said at his presidential palace in Kabul.
Portuguese President Jorge Sampaio said the prize was ''a just reward'' and ''wholly deserved.'' He singled out Carter's efforts to find a peaceful solution for East Timor, a former Portuguese colony annexed by Indonesia.
Carter, a Democrat and former Georgia governor, rose from a small-town peanut farmer to the nation's presidency in 1976 after a campaign that stressed honesty in the wake of the Watergate controversy.
But he returned home after a landslide loss to Republican Ronald Reagan in 1980, his candidacy undermined by double-digit inflation, an energy crunch that forced Americans to wait in line for gasoline, and the 444-day hostage crisis in Iran.
Carter overcame the voter repudiation and has doggedly pursued a role on the world stage as a peacemaker and champion of democracy and human rights.
He helped defuse growing nuclear tensions in Korea, then helped narrowly avert a U.S. invasion of Haiti in 1994, as well as leading conflict mediation and elections monitoring efforts around the world.
Last year's award was shared by the United Nations and its secretary-general, Kofi Annan.
I'm sooo proud. I heart Jimmy Carter muchly. He should have gotten it when Sadat and Begin did. :::hugs him:::
An added plus, if it kicks the Gee Dubya administration in the arse, so much the better.